To compare the efficacy and safety of BianTong Capsule and Maren Runchang Pill in treating constipation after neurosurgery. Methods:A total of 192 patients undergoing neurosurgery in the First Affiliated Hospital of Xi'an Jiaotong University from January 2014 to December 2016 were enrolled in the randomized controlled trial. They were randomly divided into the observation group and the control group，with 96 in each group. The observation group took Biantong capsule，3 capsules a day，2 times a day for 2 weeks，and the control group took Maren Runchang Pills，1 to 2 pills a day，2 times a day，for 2 weeks. The incidence of constipation at 72 hours after operation，the drainage volume at 3 days postoperatively，the length of hospital stay and the first defecation time，the changes of immune function at the 1st，3rd，and 7th postoperative days，and postoperative complications were recorded. Results:The incidence of constipation at the 72 h postoperatively was 2.01% in the observation group，which was significantly lower than 9.38% in the control group 9.38%. The difference between the two groups was statistically significant(P<0.05). There was no difference in drainage volume between the 2 groups on the first day after operation(P>0.05)，but the drainage volume of the observation group was lower than that of the control group on the second and third day after operation(P<0.05). The hospitalization time，drainage tube indwelling time and the first defecation time were shorter in the observation group than in the control group. The difference between the groups was statistically significant(P<0.05); the change of immune function level and postoperative complications and the adverse reactions of the 2 groups were better than the control group. There were statistically significant differences between the groups(P<0.05). Conclusion:Biantong Capsule has significant therapeutic effects on constipation after neurosurgery，and has certain regulation effects on immune function. The curative effect is better than that of Maren Runchang Pill. It has high clinical safety and is worthy of clinical application.